In many industries, such as the automotive industry, the machining industry, or other industries where parts are produced, used, and later serviced, parts removed from various machines and mechanisms often accumulate dirt or build-up in use. These parts may be covered with industrial products such as grease, paint, rust, or other elements and may require cleaning before they are reused or discarded. Industrial products, when washed in running water or in sinks connected to sewers, result in the release of industrial waste, which leads to environmental problems. These industrial wastes must often be collected and reused. Running water also has very limited utility as a cleaning fluid. Industrial solvents or other cleaning fluids, such as Safety Kleen 105 Recycled Solvent, Premium Gold Solvent, and aqueous based cleaners such as AQUAWORKS® and ARMAKLEEN® of the Safety Kleen Corp., are known to improve parts cleaning when used in a parts washer. These solvents or cleaning agents, much like industrial waste, must often be collected.
Earlier versions of parts washers are described in U.S. Pat. Nos. 3,522,814, 4,049,551, 4,261,378, 5,598,861, 5,720,308, and 7,040,161, each of which is hereby fully incorporated herein by reference. These patents generally describe parts washers wherein a sink is positioned atop or within a barrel-type reservoir and in which a submersible pump is inserted. The pump circulates cleaning fluid from the reservoir to the interior of a sink, where parts are handled by an operator for washing and scrubbing. The sink is typically equipped with a light for better illumination and inspection of the parts to be washed and a drain with a large mesh filter to prevent large objects from falling from the sink into the reservoir.
While washing is being carried out by an operator, the cleaning fluid is pumped from the reservoir and continuously drains from the opening in the bottom of the sink back into the reservoir. Ordinary cleaning tools, such as brushes, rags, and other implements, can be fitted to the end of the tube through which the cleaning fluid is dispensed and can be used by the operator during the parts cleaning operation. Over the years, the most successful parts washers have been those that can be serviced readily and economically. One such parts washer is portable and can assembled manually at any location. A drum or reservoir is moved to a location, the frame of the device is attached to the back of the reservoir, and the sink is placed on the upper rim of the reservoir.
This type of device can be readily and economically serviced. The operation consists of changing the cleaning fluid by replacing the reservoir with a new drum, changing the filter, if any, and conducting a general machine cleanup by either cycling new cleaning fluid in the device using the pump or manually cleaning the different parts of the parts washer. In use, the cleaning fluid accumulates the waste covering the parts to be cleaned. The cleaning capacity of the cleaning fluid diminishes as waste elements accumulate in the cleaning fluid. With time, the cleaning fluid liquid level in the reservoir also diminishes due to splashing and/or evaporation.
Most cleaning fluids have better cleaning properties, such as degreasing, when they are kept at a raised temperature. Heated cleaning fluids also have lower viscosity and are better adapted to dissolving elements during cleaning. Parts washers may include a heating element in the reservoir to maintain the cleaning fluid at a selected operating temperature. The heating element may also be used to offset environmental temperature if the parts washer is used outdoors or building without climate controls. A temperature sensor is used to monitor the temperature of the cleaning fluid in the reservoir and regulate the heater. Service operations include replacing the heater, the pump, the control module, or any components thereof once they no longer operate adequately or have been damaged during operation.
The present disclosure involves the discovery that known parts washers, however successful, have several disadvantages that may be further improved upon. Some cleaning fluids may become volatile at high operating temperatures. Volatility of cleaning fluids due to evaporation also impacts the liquid level in the reservoir. These cleaning fluids are better used under controlled environments to protect operators from inhalation of fumes. Most known models of sinks are of square geometry, and most reservoirs, such as drums, have an upper rim of cylindrical geometry. Other reservoirs are rectangular in shape and a sink can be partly inserted into the reservoir. An opening can be created at the interface between the sink and the reservoir that allows the cleaning fluid to evaporate. What is needed is a parts washer capable of controlling evaporation at the interface between the sink and the reservoir.
Parts washers are also used in industrial settings or other environments where collisions and impacts are to be expected, such as where a control module is located behind the sink to protect the control elements and switches from impacts when loading and unloading the mechanical parts being washed. But since access to the control module is still possible, impacts to vulnerable components of the control module are likely to occur. Impacts are also likely to occur during the servicing process if the device is mishandled or dropped. A site worker inadvertently bumping or striking the parts washer with, for instance, a piece of wood, can permanently damage the control module and/or destroy a series of control buttons on a face of the control module. What is needed is a system designed to offer delicate elements protection from impact.
Another important feature of parts washers is the liquid level of cleaning fluid within the reservoir. Once the liquid level descends below a certain threshold, not only is the pump unable to draw the cleaning fluid but the time between two consecutive cycles of use of the cleaning fluid in the work area in the sink decreases. When the reservoir is full, the cleaning fluid may, for example only, cycle into the sink every hour based on the rate and quantity of cleaning fluid pumped from the reservoir. But if the liquid level is low, the same cleaning fluid may be cycled every few minutes, precipitating the rate at which the cleaning fluid is dirtied. Current parts washers use a single liquid level detector to monitor the level of cleaning fluid in the reservoir. The detection and measurement of used cleaning fluid before it must be rejuvenated is inherently difficult and uncertain. What is needed is an improved device to measure with precision the liquid level in the reservoir.
Parts washer also rely on a pump system to circulate the cleaning fluid from the reservoir to the sink. Pumps must transport cleaning fluid that is progressively soiled by dirt, oil, or other waste suspended in the fluid. Much like the parts to be cleaned, inner sections of the pumping system, such as valves and filters, can accumulate debris, which may lead to the need for replacement of the pump and its main components. Often, foreign bodies and other sediments settle in successive layers in the reservoir. Current parts washers are equipped with horizontal pumps with part of the inlet drawing from the bottom of the reservoir at a horizontal angle in a zone where greater concentration of debris is to be anticipated. These pumps are also vulnerable to impact when the parts washer is disconnected from the reservoir during maintenance, storage, and handling. What is needed is a parts washer with an improved pump system able to filter out part of the debris in suspension using stratification properties of the cleaning fluid to protect the pump and collect debris of a size sufficient to damage the pump before the debris reaches the inner conduits of the pump while being able to pass cleaning fluid through the pump.